cell structure & function and its organelles

About cell and its organelles

1. Overview of Biochemistry BCH-311 Lecture 1

2. Introduction to Biochemistry Also known as biological Chemistry Study of biochemical reactions w ithin the living organism It is concerned with chemical c onstituents of living cells , with chemical reactions and processes they undergo

3. Continued Biochemistry explains how biological molecules like protein , carbohydrates, fats and nucleic acid give rise to different biochemical processes in cell, which turn to the complexity of life. The term biochemistry was first proposed by German scientist, Carl Neuberg in 1903.

4. Objectives of biochemistry To study and understand the structures and properties of substances constituting the framework of cells and tissues. To study the structures and properties of the substance which enter into the cell as a source of energy or leave the cell as the waste product. To study the catalytic activity of enzymes

5. Continued To study the processes that convert diet into the compounds /molecules, which are characteristics of the cells of a given specie. To study energy-requiring processes of living cell. To study the chemistry of inheritance

6. What does the biochemistry discuss? Biochemistry includes: Structure and function of cellular components such as (proteins, fats, carbohydrates, nucleic acid and other biomolecules Metabolism and regulation of cellular components Energy changes associate with these transformation Gene expression and modulation DNA RNA Protein

7. Cells Basic building block of life Smallest unit of living organism Organism may be unicellular or multicellular Cell can reproduce, use energy, adapt and respond to their environment Many cannot be seen with naked eye

8. Chemical Composition of H uman body

9. Polymers and monomers Protein, carbohydrates, fats and nucleic acids are polymers (macromolecules) and are assembled from single unit called monomers

10. Study of M etabolic P rocesses Our food consist of macromolecules such as fats, carbohydrates and proteins. First step is digestion or breakdown of these molecules into their subunits such as fatty acid & glycerol, monosaccharide's and amino acids. This is known as primary metabolism After abortion into small intestine these subunit further breakdown and oxidized to CO2, this is known as secondary metabolism. Finally reducing equivalents enters the electron transport chain and in mitochondria where they oxidized into water, this is known as tertiary metabolism.

11. Stabilizing forces in molecules Covalent bonds T he interatomic linkage that results from the sharing of an electron pair between two atoms .

12. Continued ii. Ionic or electrostatic bonds Ionic bond , type of linkage formed from the electrostatic attraction between oppositely charged ions in a chemical compound .

13. iii. Hydrogen Bonds Hydrogen bonding is a special type of dipole-dipole attraction between molecules, not a covalent bond to a hydrogen atom. It results from the attractive force between a hydrogen atom covalently bonded to a very electronegative atom such as a N, O, or F atom and another very electronegative atom .

14. iv. Hydrophobic interactions Hydrophobic interations occur between 2 or more nonpolar molecules when they're in polar environments (most commonly Water). Their 'dislike' to water causes the molecules to stick together or fold in a certain way, in order to interact with the polar environment as little as possible

15. v. Vander Waals forces Van der Waals forces are weak intermolecular forces that are dependent on the distance between atoms or molecules.

16. Water Water makes up 60-75% of human body weight . A loss of just 4% of total body water leads to dehydration, and a  loss of 15%  can be fatal. Likewise , a person could survive a month without food but wouldn’t survive 3 days without water. This crucial dependence on water broadly governs all life forms

17. Scope of biochemistry Study of cell structure and components Chemistry of carbohydrates Chemistry of inorganic elements and their deficiency. Study of enzymes Water metabolism, their sources, regulation etc. Study of vitamins and their deficiency Immunochemistry Metabolism of carbohydrates and their metabolic disorders Metabolism of proteins , amino acid their metabolic disorders Chemistry of nuclei acids, metabolism of nucleic acids Hormones and their biochemical role in body.